Observation of Her X-1 in the Hard X-Ray Range Polcaro, F. ; Bazzano, A. ; Cocchi, M. ; La Padula, C. ; Ubertini, P. ; Kendziorra, E. ; Staubert, R. Abstract Publication: International Cosmic Ray Conference Pub Date: August 1991 Bibcode: 1991ICRC....1...17P